Drill presses having noise reducing components

ABSTRACT

A drill press includes a spindle pulley having a first central opening extending along an axis, a sleeve disposed within the pulley central opening, the sleeve having a central opening aligned with the pulley central opening and the axis, and a locking nut connecting an upper end of the sleeve with the spindle pulley for supporting simultaneous rotation of the sleeve and the spindle pulley about the axis. The drill press includes a spindle disposed within the sleeve central opening and extending along the axis, the spindle being slidable along the axis relative to the sleeve and being rotatable with the sleeve. The drill press includes a spacer disposed between the spindle and the locking nut or between the spindle and the sleeve for aligning the spindle with the axis and preventing the spindle from contacting the upper end of the sleeve during rotation, which reduces noise during operation.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is generally related to power equipment, and morespecifically is related to drill presses having noise reducingcomponents.

2. Description of the Related Art

Drill presses typically include a base, a vertical support columnextending upwardly from the base, a table attached to a mid-section ofthe vertical support column for holding work pieces, and a head stocksecured to an upper end of the vertical support column. The head stockincludes a rotatable handle that is turned for moving a spindle up anddown along a vertical axis that is parallel with the longitudinal axisof the vertical support column. The height of the table may be adjustedusing a second rotatable handle coupled with a rack and pinion system.The table may be rotated about the longitudinal axis of the supportcolumn to offset the table from the vertical axis of the spindle. Insome designs, a drill chuck for holding a drill bit is connected to alower end of the spindle. The drill chuck may have three jaws that holdan upper end of the drill bit in the chuck. Some drill presses include aspindle having a lower end with a tapered opening for receiving a drillbit having a tapered shaft that fits into the tapered opening. When thedrill press is activated, a motor rotates pulleys via one or more drivebelts, which, in turn, rotate the spindle and the drill bit secured tothe lower end of the spindle.

Drill presses provide many advantages over hand-held drills. First, thespindle is moved up and down along a vertical axis by a rotatable handlecoupled with a rack and pinion system, which provides an operator withconsiderable mechanical advantage. Thus, less effort is required toadvance the drill bit through a work piece. Second, a drill press has atable for supporting a work piece, which enables a vice grip or clamp tobe used to hold the work piece in an immoveable position on the table.In addition, the spindle moves along a fixed vertical axis relative tothe top surface of the table, which allows operators to accurately drillholes in work pieces.

Many drill presses have a mechanism for changing the speed of rotationof the drill. Often, the speed is changed by manually moving one or moredrive belts across a stepped pulley arrangement. In one conventionaldesign, in order to change the speed, an operator must first move themotor to provide sufficient slack in at least one of the drive belts.After the drive belts are repositioned, the motor is moved back to itsinitial position for tensioning the drive belts. Moving the motorrequires that the motor be mounted in such a way that it may betranslated to allow for belt tensioning. This mounting arrangement maycause unwanted noise and vibration if the machining of the drill pressis not precise. Recently, some drill presses have added a third steppedpulley to increase the range of speeds. Some drill presses are equippedwith a variable speed motor or a continuously variable transmission,which enable operators to change speeds while the machine is running.

FIGS. 1A and 1B show a conventional drill press including a drive systemfor driving a spindle. The drive system includes a stepped spindlepulley 10 that is driven by a drive belt 12. The stepped spindle pulley10 is rotatably mounted to a head stock 14 of a drill press and includesan upper end 16, a lower end 18 and a series of steps 20 ofprogressively larger diameter extending between the upper end and thelower end. Referring to FIG. 1B, the stepped spindle pulley 10 includesa central opening 22 extending between the upper end 16 and the lowerend 18 thereof. The central opening 22 is adapted to receive a sleeve 24that rotates simultaneously with the stepped spindle pulley 10. Alocking nut 25 couples the stepped spindle pulley 10 with the sleeve 24.The sleeve 24 has an upper end 26 having a larger diameter opening and alower end 28 having a smaller diameter opening that is smaller than thelarger diameter opening at the upper end 26. The drive system includes aspindle 30 that is adapted for reciprocating movement along a verticalaxis A₁. Thus, the spindle 30 may be extended and retracted relative tothe sleeve 24 along the vertical axis A₁. Referring to FIG. 1A, thespindle 30 has an outer surface including a plurality of splines 32 thatextend along the axial length thereof. The splines 32 mesh with thesecond smaller diameter opening at the lower end 28 of the sleeve 24. Asa result, the splined spindle 30 is able to move along the vertical axisA₁ relative to the sleeve 24, however, the meshing of the smallerdiameter opening of the sleeve 24 with the splines 32 on the spindle 30transmits rotational movement from the sleeve 24 to the spindle 30.

In conventional drill presses, there is excessive clearance between thelarger diameter opening at the sleeve upper end 26 and the spindle outersurface. As a result, when the drill press is operated with the spindle30 in the retracted position shown in FIG. 1B, the rotating spindle 30knocks against the sleeve at a high frequency, which creates a rattlingnoise. The rattling noise tends to disappear when the spindle 30 islowered along the vertical axis A₁ toward a work piece supporting table,which only makes the noise that much more obvious to operators when thespindle is once again retracted.

In view of the above deficiencies, there is a need for drill pressesthat have noise reducing components, and which are quieter when beingoperated.

SUMMARY OF THE INVENTION

In one embodiment, a drill press having noise reducing componentsdesirably includes a spindle pulley having a central opening extendingalong an axis, the spindle pulley being rotatable about the axis, and asleeve disposed within the pulley central opening, the sleeve having acentral opening aligned with the pulley central opening and the axis.The drill press preferably includes a locking nut connecting an upperend of the sleeve with the spindle pulley for supporting simultaneousrotation of the sleeve and the spindle pulley. A spindle is desirablydisposed within the sleeve central opening of the sleeve and extendsalong the axis, whereby the spindle is slidable along the axis relativeto the sleeve and is rotatable with the sleeve about the axis. The drillpress desirably includes a spacer disposed between the spindle and thelocking nut for aligning the spindle with the axis and for preventingthe spindle from contacting the sleeve upper end during rotation of thespindle and the sleeve about the axis.

In one embodiment, the sleeve has the upper end, a lower end, and thesleeve central opening extends between the upper and lower ends of thesleeve. The sleeve central opening preferably has a larger diametersection adjacent the sleeve upper end and a smaller diameter sectionadjacent the sleeve lower end.

In one embodiment, the spindle preferably has an elongated spindle shaftwith a length aligned with and extending along the axis. The spindledesirably includes splines that extend along the length of the elongatedspindle shaft. The splines are desirably adapted to mesh with thesmaller diameter section at the sleeve lower end for transmittingrotation forces from the sleeve to the spindle shaft. In one embodiment,the sleeve smaller diameter section has a plurality of protrusionsadapted to mesh with the spindle shaft splines for transmittingrotational forces from the sleeve to the spindle shaft. The splinesdesirably define an outer diameter of the spindle shaft that is smallerthan the sleeve larger diameter section.

In one embodiment, the sleeve upper end desirably has external threadsadapted to mesh with internal threads on the locking nut. The lockingnut preferably has a central aperture aligned with the axis, and thespindle is slidable along the axis relative to the locking nut. In oneembodiment, the spacer is ring-shaped (e.g. shaped like a grommet) andis secureable within the locking nut central aperture. The spacerdesirably has a central aperture aligned with the axis, whereby thespindle is adapted to slide along the axis relative to the spacer.

In one embodiment, the locking nut has an annular projection thatextends into the locking nut central aperture and the ring-shaped spacerhas an outer surface including an annular groove that is adapted toreceive the locking nut annular projection. In one embodiment, thespacer is desirably made of a non-metallic material such as rubber,polymers, and elastic materials, and the locking nut may be made ofmetal such as steel.

In one embodiment, a drill press having at least one noise reducingcomponent includes a spindle pulley having an axis and a central openingextending along the axis, a sleeve disposed within the pulley centralopening, the sleeve having a central opening aligned with the axis, andan elongated spindle disposed within the sleeve central opening andbeing aligned with the axis, the elongated spindle being adapted toslide along the axis relative to the sleeve and the spindle pulley, andthe elongated spindle being adapted to rotate simultaneously with thesleeve and the spindle pulley. The drill press preferably includes alocking nut for connecting an upper end of the sleeve with the spindlepulley. The locking nut preferably has a central aperture aligned withthe pulley central opening and the sleeve central opening, whereby thespindle extends through the locking nut central aperture. The drillpress desirably includes a spacer disposed between an outer surface ofthe spindle and the locking nut central aperture for preventing thespindle from contacting the upper end of the sleeve during rotation ofthe sleeve and the spindle about the axis.

In one embodiment, the sleeve preferably has an upper end, a lower end,and the sleeve central opening between the upper and lower ends. Thesleeve central opening desirably has a larger diameter section adjacentthe sleeve upper end adapted for enabling the spindle to slide along theaxis relative to the sleeve, and a smaller diameter section adjacent thesleeve lower end adapted to mesh with the spindle for transmittingrotation forces between the sleeve and the spindle while enabling thespindle to slide along the axis relative to the sleeve. The spindlepreferably includes splines extending along a length of the spindle. Thesplines are preferably adapted to mesh with the smaller diameter sectionof the sleeve central opening for transmitting rotation forces from thesleeve to the spindle. The smaller diameter section of the sleevepreferably includes protuberances for transmitting rotational forcesfrom the sleeve to the spindle. The splines are able to slide throughthe protuberances for enabling axial movement of the spindle relative tothe sleeve.

These and other preferred embodiments of the present invention will bedescribed in more detail below.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1A shows a perspective view of a conventional drive system for adrill press including a stepped spindle pulley and a spindle, inaccordance with one embodiment of the present invention.

FIG. 1B shows a cross-sectional view of the prior art stepped spindlepulley and spindle shown in FIG. 1A.

FIG. 2 shows a perspective view of a drill press including a head stock,a vertical support column, a stand, and a work piece supporting table,in accordance with one embodiment of the present invention.

FIG. 3A shows a top perspective view of a drive system for the drillpress shown in FIG. 2 including drive belts, a motor pulley, a centerpulley, a spindle pulley coupled with a spindle, and a noise reducingcomponent coupled with the spindle, in accordance with one embodiment ofthe present invention.

FIG. 3B shows a front perspective view of the drive system shown in FIG.3A, in accordance with one embodiment of the present invention.

FIG. 4A shows a cross-sectional view of the spindle pulley, the spindleshaft and the noise reducing component shown in FIGS. 3A and 3B, inaccordance with one embodiment of the present invention.

FIG. 4B shows a cross-section of FIG. 4A taken along line 4B-4B thereof.

FIG. 4C shows a cross-section of FIG. 4A taken along line 4C-4C thereof.

FIGS. 5A-5C show a locking nut for a drill press, in accordance with oneembodiment of the present invention.

FIG. 6 shows a perspective view of a spacer and the spacer coupled withthe locking nut of FIGS. 5A-5C, in accordance with one embodiment of thepresent invention.

FIG. 7A shows the drive system of FIGS. 3A-3B and 4A with the spindle ina retracted position, in accordance with one embodiment of the presentinvention.

FIG. 7B shows the drive system of FIGS. 3A-3B and 4A with the spindle inan extended position, in accordance with one embodiment of the presentinvention.

FIG. 8 shows a cross-sectional view of a noise reducing componentengaging a spindle of a drill press, in accordance with one embodimentof the present invention.

DETAILED DESCRIPTION

Referring to FIG. 2, in one embodiment, a drill press 40 preferablyincludes a head stock 42 supported atop a vertically-extending supportcolumn 44 and a stand 46 supporting a lower end of the support column44. The drill press desirably includes a rotatable spindle 48 projectingfrom a lower end of the head stock 42 and a chuck 50 mounted to a lowerend of the spindle. The chuck is preferably adapted to receive a drillbit 52 used for drilling holes in work pieces. The drill press desirablyincludes a rotatable handle 54 that may be engaged for lowering therotatable spindle 48, the chuck 50 and the drill bit 52 along a verticalaxis A₂ that is parallel with the longitudinal axis of the supportcolumn 44. The drill press 40 also preferably includes a table 56 havinga top surface 58 adapted to support a work piece below the spindle 48,the chuck 50, and the drill bit 52. The drill press preferably includesa table adjustment handle 60 that may be operated for raising andlowering the table 56 along the support column 44 using a rack andpinion arrangement.

The head stock 42 preferably includes a head stock pulley cover 62 thatcovers a drive system for supplying power to the spindle 48. In oneembodiment, the drive system preferably includes a motor 64 that iscoupled with the spindle 48 via one or more pulleys and drive belts, aswill be described in more detail below. The head stock cover 62 isdesirably moveable between the closed position shown in FIG. 2 and anopen position for accessing the drive belts and rotatable pulleyslocated between the motor 64 and the spindle 48. In one embodiment, theposition of the drive belts on the pulleys may be changed for modifyingthe speed of the drill press.

Referring to FIGS. 3A and 3B, in one embodiment, the head stock cover 62may be opened for exposing a portion of the drive system of the drillpress. In one embodiment, the drive system preferably includes a steppedmotor pulley 66 that is rotated by a motor shaft 68 coupled with themotor 64 (FIG. 2). In one embodiment, a stepped center pulley 70 isrotatably mounted on a center pulley shaft 71. A lower end of the centerpulley shaft is preferably mounted to the head stock via a pivoting arm72 that desirably enables the position of the center pulley 70 to beselectively shifted for changing the positions of the drive belts 74,82. In one embodiment, the center pulley 70 is a stepped pulley havingfive steps of varying radii.

The drive system preferably includes a first drive belt 74 that extendsabout the motor pulley 66 and the center pulley 70. In one embodiment,the first drive belt 74 is preferably adapted to transmit power from themotor pulley 66 to the center pulley 70. In one embodiment, the firstdrive belt 74 is preferably a poly-v drive belt with v-shaped groovesformed on an inner face thereof, and the stepped pulleys have v-shapedgrooves or projections adapted to mesh with the v-shaped grooves on thedrive belts. In another embodiment, the drive belts may be conventionaldrive belts having a smooth inner face and the pulleys may have smoothstepped surfaces that mesh with the smooth inner faces of the drivebelts. In other embodiments, any type of drive belt well-known to thoseskilled in the art may be used.

In one embodiment, the drive system preferably includes a steppedspindle pulley 76 that is coupled with the spindle 48 having anelongated shaft 78 and splines 80 extending along the axial length ofthe elongated shaft 78. The drive system preferably includes a seconddrive belt 82 that interconnects the rotatable center pulley 70 with thespindle pulley 76.

In one embodiment, the drive system preferably includes a spring-loadeddrive belt tensioner 84 that is adapted to apply tension to an outersurface or face of one of the drive belts, such as disclosed in commonlyassigned U.S. patent application Ser. No. 12/813,554, filed Jun. 11,2010, the disclosure of which is hereby incorporated by referenceherein. In one embodiment, the spring loaded tensioner 84 desirablyapplies tension to the outer face of the first drive belt 74. In oneembodiment, the spring-loaded tensioner 84 uses spring force forautomatically and continuously applying tension to the slack side and/orouter surface of the first drive belt 74 to maintain optimum tension onthe first drive belt. As such, the motor associated with the motorpulley 66 may be rigidly mounted to the drill press, thereby eliminatingseveral parts previously required in prior art systems for shifting theposition of the motor for changing speeds, as well as the previouslyrequired extra machining on the head stock casting. Other benefitsdesirably include insuring that proper belt tension will always bemaintained on the drive belts 74, 82, thereby eliminating user errorwhen attempting to set the tension on the drive belts.

In one embodiment, the tensioner preferably applies tension to the slackside of the first drive belt 74. In one embodiment, the spring-loadedtensioner may be rotated in a counter-clockwise direction designated R₁for lessening the amount of tension applied by the tensioner 84 to thefirst drive belt 74 so that the position of at least one of the firstand second drive belts 74, 82 may be changed for modifying the speed ofthe drill press. In one embodiment, zero tension is applied to the firstdrive belt 74 when the tensioner 84 is retracted. After the position ofat least one of the first and second drive belts has been modified forchanging the speed of the drive system, the spring-loaded tensioner maybe rotated a clockwise direction designated R₂ so that the belttensioner 84 re-engages the first drive belt 74 for applying tension tothe drive system. The tensioner preferably includes a spring thatnormally urges the tensioner 84 to rotate in the direction R₂.

In one embodiment, the tension force applied by the spring-loadedtensioner 84 to the poly-V belt is according to the belt manufacturer'srequirements. In one preferred embodiment, the spring-loaded tensioner84 preferably engages the slack side of the first drive belt.

In one embodiment, the motor shaft 68 rotates the motor pulley 66 fordriving the first drive belt 74. In turn, the first drive belt 74rotates the center pulley 70 about the center pulley shaft 71. As thecenter pulley 70 rotates, the center pulley drives the second drive belt82, which, in turn, rotates the spindle pulley 76. Rotation of thespindle pulley simultaneously rotates the spindle shaft 78, the chuck 50and the drill bit 52 (FIG. 2) secured to the chuck. In one embodiment,the position of the first drive belt and the second drive belt on thestepped pulleys may be adjusted for changing the speed of rotation ofthe spindle.

Referring to FIGS. 3B and 4A, in one embodiment, the splined spindleshaft 78 is adapted to move upward and downward along the vertical axisA₂. The splined spindle shaft 78 preferably moves upward when beingretracted and downward when being extended. The splines 80 extendingalong the outer surface of the spindle shaft 78 preferably mesh with asmaller diameter section at a lower end of a sleeve, as will bedescribed in more detail herein.

Referring to FIG. 4A, in one embodiment, the drive system preferablyincludes the stepped spindle pulley 76 having an upper end 90, a lowerend 92 and a series of steps 94 of progressively larger diameterextending between the upper end 90 and the lower end 92. The steppedspindle pulley 76 preferably includes a central opening 96 that extendsbetween the upper and lower ends 90, 92 thereof. The pulley centralopening 96 is desirably aligned with the vertical axis A₂. The pulleycentral opening 96 is adapted to receive a tubular shaped or elongatedsleeve 98 that is preferably coupled with the stepped spindle pulley 76for rotating simultaneously with the stepped spindle pulley. The sleeve98 desirably includes an upper end 100 and a lower end 102. The sleeveupper end 100 preferably defines a larger diameter section 104 having afirst radius R₁. The sleeve lower end 102 preferably defines a smallerdiameter section 106 including projections 107 having a second radius R₂that is smaller than the first radius R₁. The splines 80 extend alongthe longitudinal axis A₂ of the spindle shaft 78 so that the spindleshaft may move along axis A₂ relative to the sleeve 98 for beingextended and retracted. The projections defining the smaller diametersection 106 at the sleeve lower end 102 preferably mesh with the splines80 extending along the outer surface of the spindle shaft 78 so thatrotation of the sleeve 98 results in rotation of the spindle shaft 78.

FIG. 4B shows a cross-section of the upper end 100 of the sleeve 98including the larger diameter section 104 having a first radius R₁,which is spaced from the splines 80 on the outer surface of the spindleshaft 78. FIG. 4C shows a cross-section of the lower end 102 of thesleeve 98 including the projections 107 defining the smaller diametersection 106 that mesh with the splines 80 extending along the outersurface of the spindle shaft so that the rotating sleeve 98 transmitsrotational force to the spindle shaft 78.

As noted herein, the elongated sleeve 98 is preferably affixed withinthe first central opening 96 of the stepped spindle pulley 76. As aresult, when the stepped spindle pulley 76 is rotated by a drive belt 82(FIG. 3B), the sleeve 98 rotates simultaneously with the stepped spindlepulley 76.

In one embodiment, the drive system preferably includes a spacer 110having an axial opening 112 or central aperture. The spacer 110 ispreferably adapted to slide over the outer surface of the spindle shaft78 for assembling the spacer and a locking nut 120 together. The drivesystem preferably includes the locking nut 120 that is secured over thesleeve upper end 100. The locking nut 120 preferably couples the spindlepulley and the sleeve 98 together for simultaneous rotation. In oneembodiment, the spacer 110 includes an outer surface having an annulargroove 114 and the locking nut 120 includes an annular projection 124that sits within the spacer annular groove 114. The spacer may bering-shaped and may be made of non-metallic materials such as rubber,polymers and elastic materials. In one embodiment, the spacer may be agrommet.

In one embodiment, the central aperture of the spacer 110 defines arounded, annular or ring-shaped inner surface. In one embodiment, thecentral aperture of the spacer 110 has a plurality of elongated groovesformed therein that are adapted to receive splines on an outer surfaceof the spindle. The elongated grooves formed within the central apertureof the spacer 110 preferably closely conform with and/or interface withthe splines on the outer surface of the spindle as the spindle movesalong a vertical axis relative to the spacer. In one embodiment, thespindle and the spacer are adapted to rotate simultaneously with oneanother about the vertical axis.

In one embodiment, the spacer 110 preferably includes an outer surfacehaving an annular projection and the locking nut 120 has an innersurface including an annular groove that is adapted to receive theannular projection for coupling the spacer and the locking nut together.In one embodiment, the spacer 110 includes an outer surface having anannular groove with an O-ring disposed in the annular groove and thelocking nut 120 has an inner surface including an annular groove that isadapted to receive the O-ring attached to the spacer for coupling thespacer and the locking nut together.

In one embodiment, the spacer 110 is positioned between the outersurface of the spindle and the locking nut for preventing the rotatingspindle from rattling against the sleeve. In one embodiment, the spacermay be positioned between the upper end of the sleeve and the spindlefor preventing the rotating spindle from rattling against the sleeve,such as by incorporating the spacer into the upper end of the sleeve.

Although the present invention is not limited by any particular theoryof operation, it is believed that using a spacer that fits around aspindle shaft 78 for aligning it with the sleeve 98 prevents contactbetween the rotating spindle shaft 78 and the sleeve 98 for reducingnoise found in prior art systems. In one embodiment, the spacer 110 ispreferably made of a material that is soft enough to firmly hold ontothe spindle shaft 78, while enabling the rotating spindle shaft 78 tofreely move along the vertical axis A₂. In one embodiment, using aspacer 110 between the locking nut 120 and the spindle shaft 78preferably produces a drill press that is extremely quiet and thatabsorbs any manufacturing tolerances between the parts, particularlybetween the sleeve 98 and the spindle shaft 78. In one embodiment, theuse of the spacer 110 and the locking nut 120 preferably reduces thenoise level of an operating drill press to at least 2-5 decibels lowerthan may be obtained when using conventional drill presses, therebyproviding a much quieter drill press.

Referring to FIGS. 5A-5C, in one embodiment, the locking nut 120preferably includes an upper end 122 having an annular projection 124that bounds a central aperture 126 extending between the upper end 122and a lower end 128 of the locking nut. Referring to FIG. 5A, thelocking nut 120 includes internal threads 130 that bound the centralaperture 126 adjacent the locking nut lower end 128. The internalthreads 130 are preferably adapted to mesh with external threads at anupper end of the sleeve for coupling the locking nut 120 with the sleeve98 (FIG. 4A). Referring to FIGS. 5A and 5C, the locking nut 120desirably includes a pocket 132 positioned between the annularprojection 124 and the lower end 128 of the locking nut 120. The annularprojection 124 is adapted to sit within an annular groove 114 formed inthe outer surface of the spacer 110 for holding the spacer within thepocket 132.

Referring to FIG. 5C, the locking nut central aperture 126 preferablyincludes a smaller diameter section 134 adjacent the upper end 122 ofthe locking nut 120 and a larger diameter section 136 adjacent the lowerend 128 of the locking nut 120. The smaller diameter section 134preferably conforms to the outer diameter of the annular groove of thespacer. The larger diameter section 136 preferably conforms to the outerdiameter of the upper end of the sleeve.

In one embodiment, the outer portion of the locking nut 120 has wrenchflats or other features which allow the locking nut to be properlyassembled and/or torqued, with an inner diameter suitable for forming amating fit with a grommet or other elastomeric material, and a heightsufficient to accommodate the grommet and provide satisfactory clampingforce on the pulley. Referring to FIG. 5B, in one embodiment, thelocking nut 120 preferably has a width OD across the flats of about 1.25inches. Referring to FIG. 5C, in one embodiment, the pocket 132 of thelocking nut 120 has an inner diameter ID of about 0.75 inches. In oneembodiment, the locking nut has a height H of about 1.0 inches.

FIG. 6 shows a perspective view of the ring-shaped spacer 110. Thering-shaped spacer 110 desirably includes a central aperture 112 that issized to enable axial movement of the spindle shaft 78 (FIG. 4A)relative to the spacer. An outer surface of the ring-shaped spacer 110includes an annular groove 114 that is adapted to mesh with the annularprojection 124 adjacent the upper end 122 of the locking nut 120 (FIG.5A). The left side of FIG. 6 shows the locking nut 120 after thering-shaped spacer 110 has been assembled with the locking nut. An upperend of the spacer 110 lies above the upper end 122 of the locking nut120. The locking nut internal threads 130 extend around the locking nutcentral aperture 126 adjacent the locking nut lower end 128.

FIG. 7A shows the ring-shaped spacer 110 and the locking nut 120 securedto the upper end 90 of the stepped spindle pulley 76. In FIG. 7A, thesplined spindle shaft 78 is in a retracted position whereby the drillbit 52 (FIG. 2) is retracted away from the top surface 58 of the table56. FIG. 7B shows the splined spindle shaft 78 in an extended positionso that only an upper end of the splined spindle shaft 78 is visiblethrough the spacer 110 and the locking nut 120. The locking nut 120preferably couples the spindle pulley 76 with the sleeve upper end 100(FIG. 4A).

FIG. 8 shows a cross-sectional view of the spacer 110 and the lockingnut 120 that clearly depicts how the locking nut couples the componentstogether. In FIG. 8, the spindle pulley has been removed so that thesleeve upper end 100 may be clearly shown. The sleeve upper end 100includes external threads 105 that mesh with the internal threads 130 atthe locking nut lower end 128. The locking nut 120 includes an upper end122 having an annular projection 124 that is seated in the annulargroove 114 formed in the outer surface of the spacer 110. The spacer 110includes a central aperture 112 that receives the splined spindle shaft78. The splined spindle shaft 78 is free to move along the axis A₂relative to the spacer 110, the locking nut 120, and the sleeve 98. Thespacer 110 and the locking nut 120 desirably cooperate to space theouter surface of the spindle shaft 78 away from the inner surface of thesleeve 100 so as to prevent the rotating spindle shaft 78 from knockingand/or rattling against the sleeve upper end 100 during operation of thedrill press, thereby minimizing noise present in prior art systems whenthe rotating spindle shaft knocks and/or rattles against the sleeve.

The headings used herein are for organizational purposes only and arenot meant to limit the scope of the description or the claims. As usedthroughout this application, the word “may” is used in a permissivesense (i.e., meaning having the potential to), rather than the mandatorysense (i.e., meaning must). Similarly, the words “include”, “including”,and “includes” mean including but not limited to. To facilitateunderstanding, like reference numerals have been used, where possible,to designate like elements common to the figures.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, which is only limited by thescope of the claims that follow. For example, the present inventioncontemplates that any of the features shown in any of the embodimentsdescribed herein, or incorporated by reference herein, may beincorporated with any of the features shown in any of the otherembodiments described herein, or incorporated by reference herein, andstill fall within the scope of the present invention.

What is claimed is:
 1. A drill press comprising: a spindle pulley havinga central opening extending along an axis, said spindle pulley beingrotatable about said axis; a sleeve disposed within said pulley centralopening, said sleeve having a central opening aligned with said pulleycentral opening and said axis; a locking nut connecting an upper end ofsaid sleeve with said spindle pulley for supporting simultaneousrotation of said sleeve and said spindle pulley; a spindle disposedwithin said sleeve central opening and extending along said axis, saidspindle being slidable along said axis relative to said sleeve and beingrotatable with said sleeve about said axis; a spacer disposed betweensaid spindle and said locking nut for aligning said spindle with saidaxis and for preventing said spindle from contacting said sleeve upperend during rotation of said spindle and said sleeve about said axis. 2.The drill press as claimed in claim 1, wherein said sleeve has saidupper end, a lower end, and said sleeve central opening extends betweensaid upper and lower ends of said sleeve.
 3. The drill press as claimedin claim 2, wherein said sleeve central opening has a larger diametersection adjacent said sleeve upper end and a smaller diameter sectionadjacent said sleeve lower end.
 4. The drill press as claimed in claim3, wherein said spindle has an elongated spindle shaft with a lengthaligned with and extending along said axis.
 5. The drill press asclaimed in claim 4, wherein said spindle comprises splines extendingalong the length of said elongated spindle shaft.
 6. The drill press asclaimed in claim 5, wherein said splines are adapted to mesh with saidsleeve smaller diameter section at said sleeve lower end fortransmitting rotation forces from said sleeve to said spindle shaft. 7.The drill press as claimed in claim 6, wherein said sleeve smallerdiameter section comprises a plurality of protrusions adapted to meshwith said spindle shaft splines for transmitting rotation forces fromsaid sleeve to said spindle shaft.
 8. The drill press as claimed inclaim 7, wherein said splines define an outer diameter of said spindleshaft that is smaller than said larger diameter section.
 9. The drillpress as claimed in claim 1, wherein said sleeve upper end has externalthreads adapted to mesh with internal threads on said locking nut. 10.The drill press as claimed in claim 9, wherein said locking nut has acentral aperture aligned with said axis, and wherein said spindle isslidable along said axis relative to said locking nut.
 11. The drillpress as claimed in claim 10, wherein said spacer is ring-shaped and issecureable within said locking nut central aperture.
 12. The drill pressas claimed in claim 11, wherein said spacer has a central aperturealigned with said axis, and wherein said spindle is adapted to slidealong said axis relative to said spacer.
 13. The drill press as claimedin claim 12, wherein said locking nut has an annular projection thatextends into said locking nut central aperture and said ring-shapedspacer has an outer surface including an annular groove that is adaptedto receive said locking nut annular projection.
 14. The drill press asclaimed in claim 1, wherein said spacer comprises a non-metallicmaterial selected from the group consisting of rubber, polymers andelastic materials.
 15. The drill press as claimed in claim 1, whereinsaid spacer has a central aperture adapted to receive said spindle. 16.The drill press as claimed in claim 16 wherein said central aperture ofsaid spacer defines an annular surface or a surface having a pluralityof elongated grooves adapted to mesh with splines on said spindle.
 17. Adrill press comprising: a spindle pulley having an axis and a centralopening extending along said axis; a sleeve disposed within said pulleycentral opening, said sleeve having a central opening aligned with saidaxis; an elongated spindle disposed within said sleeve central openingand being aligned with said axis, said elongated spindle being adaptedto slide along said axis relative to said sleeve and said spindlepulley, and said elongated spindle being adapted to rotatesimultaneously with said sleeve and said spindle pulley; a locking nutfor connecting an upper end of said sleeve with said spindle pulley,said locking nut having a central aperture aligned with said pulleycentral opening and said sleeve central opening, wherein said spindleextends through said locking nut central aperture; a spacer disposedbetween an outer surface of said spindle and said locking nut centralaperture for preventing said spindle from contacting said sleeve upperend during rotation of said sleeve and said spindle about said axis. 18.The drill press as claimed in claim 17, wherein said locking nutcomprises metal and said spacer comprises a non-metal.
 19. The drillpress as claimed in claim 17, wherein said sleeve has an upper end, alower end, and said sleeve central opening extends between said upperand lower ends, wherein said sleeve central opening has a largerdiameter section adjacent said sleeve upper end adapted for enablingsaid spindle to slide along said axis relative to said sleeve, and asmaller diameter section adjacent said sleeve lower end adapted to meshwith said spindle for transmitting rotation forces between said sleeveand said spindle while enabling said spindle to slide along said axisrelative to said sleeve.
 20. The drill press as claimed in claim 19,wherein said spindle comprises splines extending along a length of saidspline, and wherein said splines are adapted to mesh with said smallerdiameter section of said sleeve central opening for transmittingrotation forces from said sleeve to said spindle.
 21. The drill press asclaimed in claim 17, wherein said spacer is ring-shaped and issecureable within said locking nut central aperture.